1. Field of the Invention
The present invention relates to solid-state storage subsystems. More specifically, the present invention relates to providing data redundancy within a solid-state storage subsystem.
2. Description of the Related Art
Companies are increasingly relying on portable solid-state storage subsystems to persistently store executable code and data. Typically, these subsystems are in the form of a memory card or drive that connects to an external port or connector of a host computer system. Because solid-state storage subsystems tend to be lighter, smaller and more shock resistant than magnetic disk drives, they are especially useful for applications involving portability. In many cases, the solid-state storage subsystem is used by the host system as a boot device (i.e., it stores the operating system code executed by the host computer), and/or is used to persistently store data generated or captured by the host computer.
One problem with existing solid-state storage subsystems is that they typically do not provide a sufficient degree of protection against data losses. Such data losses are typically caused by memory wear, memory array controller malfunctions, or rampant host software that overwrites important data. When such data losses occur, they can result in significant down time and lost revenue, especially if the storage subsystem is used to store operating system files or critical data.